1. Technical Field
The present disclosure relates generally to a spinal plate and, more particularly, to a dynamic cervical plate.
2. Background of Related Art
The human spinal column is a highly complex structure. It includes more than twenty discrete bones, known as vertebrae, coupled sequentially to one another to house and protect critical elements of the nervous system. The cervical portion of the spine, which comprises the top of the spine up to the base of the skull, includes the first seven vertebrae.
For many reasons, such as aging and trauma, the intervertebral discs can begin to deteriorate and weaken, potentially resulting in chronic pain, degenerative disc disease, or even tearing of the disc. Ultimately, the disc may deteriorate or weaken to the point of tearing and herniation, in which the inner portions of the disc protrude through the tear. A herniated disc may press against, or pinch, the spinal nerves, thereby causing radiating pain, numbness, tingling, and/or diminished strength or range of motion.
Many treatments are available to remedy these conditions, including surgical procedures in which one or more damaged intervertebral discs are removed and replaced with a prosthetic. However, should the prosthetic protrude from between the adjacent vertebrae and thereby contact the surrounding nerves or tissues, the patient may experience additional discomfort. In procedures for remedying this problem, a spinal plate is affixed to the vertebrae and oriented to minimize such protrusion.
Spinal plates, and cervical plates in particular, are known in the art. Fixed cervical plates generally exhibit unalterable, static dimensions. During the natural subsidence of the spinal column over time, its overall length gradually decreases. Fixed cervical plates resist this change due to their fixed axial length, which may eventually stress the spine and cause pain or discomfort. Adjustable cervical plates attend to this predicament by providing a mechanism through which the plate is shortened to accommodate for a measure of subsidence. However, the known adjustable plates require subsequent surgical procedures to adjust the axial dimension of the plate.